[Benjammer]

IMO, It's just a different approach to the idea than the React world. I would assume the idea here is that you always want to write your UI layer "natively" in order to take full advantage of platform-specific performance accelerations/hardware APIs, but the entire stack underneath what's actually rendering visual components would be shared.

It forces you to start out more modular between your UI code and domain logic code, whereas React (& React Native) leaves the door open right at the start for tight coupling between UI code & domain logic, unless you expressly build this separation into your initial architecture.